aaaa aaab aaac aaar aaba aabb aabc aabt aaca aacb aacc aacr aact aara aarc aart aata aatc aatt abaa abab abac abar abat abb- abba abbb abbr abbt abca abcb abcc abcr abct abra abrc abta ac-t acaa acab acac acar acat acba acca accc acct acr- acra acrc acrr acta actc actt arab arac arar arat arba arc- arca arct arr- arra arrc arrr arrt arta artc artr at-t ataa atab atac atar atat atca atcc atcr atra atrc atta attr baaa baar baat baba babb babr bac- baca bacc bact bar- bara barb barc barr bart bata batc batt bbbb bbrc bcaa bcar bcat bcbc bcca bccc bcra bctc brab brac brat brca brcb brrr brtc btaa btcc btrc btrt bttb caaa caab caac caat caba cac- caca cacc cacr cara carb carc carr cart cat- cata catb catc catt cbac cbar cbat cbbc cbca cbcc cbcr cbct cbrt cbta cbtc ccaa ccab ccac ccar ccat ccba ccbc ccca cccb cccc ccra ccrc ccrt cctb cctc cctt crab crac crar crat crbc crca crcc crcr crrt crtc ctab ctba ctca ctrc ctta raab raat raba rabb rac- raca racc ract rara rarb rata ratt rbbb rbbr rcac rcbc rccb rccc rctc rrat rrrr rtca rtcc taa- taar taat taba tabb tabc taca tacc tact tara tarb tarc tarr tart tata tatb tatr tatt tbar tbca tbcb tbcc tbrb tbta tcca tccc tctc traa trab trac trat trca trcc trra trtc trtr ttab ttbb tttt